Surgical approach to intramyocardial administration of bone marrow stem cells in an animal model

Abstract AIM: The aim of the study was to evaluate the surgical approach to intramyocardial (i.m.) injection of Bone Marrow Stem Cells (BMSCs) in a pre-clinical model and its complications. MATERIAL OF STUDY: In New Zealand rabbits an ischemia reperfusion injury lasting 20 min was induced by temporary ligation of anterior descending coronary artery during cardiac surgical procedure. Homologous BMSCs were isolated from the posterior iliac crest, cultured and re-suspended for injection. BMSC were injected at the peri-infarcted area and side effects were evaluated. A control group with myocardial infarction was treated with i.m. injections of saline, to evaluate possible side effects of injection. Comparison of ventricular premature contractions (VPC), ventricular tachycardia and ventricular fibrillation were recorded during surgery and after 7 and 21 days. RESULTS: Seven rabbits developed intractable ventricular fibrillation during the experimental protocol, three during coronary ligation but before cell injections and four following i.m. injections. At day 7, hourly PVC were more frequent in the groups of animals that received i.m. injections of BMSCs (132 +/- 19 beats) compared to saline injections. (54 +/- 14). CONCLUSIONS: Intramyocardial injections of BMSCs induced an electrical instability as shown by a high number of PVC as compared with intramyocardial injections of saline.